Position light



C. ADLER, JR

POSITION LIGHT Aug. 17, 1948.

2 Sheets-Sheet 1 Fil ed Sept. 29, 1947 Aug. 17, 1948. ADLER, JR 2,447,302

POSITION LIGHT Fil ed Sept. 29, 1947 2 Sheets-Sheet 2 vided and that a candle power also be made available. The imporangular relationship between shown in Figure 6 with i atented Aug. 17, E43

2,4413% POSITION LIGHT Charles Adler, Jr., Baltimore, Md.

Application September 29,

1947, Serial No. 716,673

3 Claims. (01. 2404.7)

This invention relates to aircraft position lights, and, more particularly, to an improved tail light.

- Position lights for aircraft, notably, tail lights,

require that a substantial light spread be pro-, light of highest possible beam tance of these tworequirements increases as the the flight paths of overtaking and preceding aircraft becomes smaller, 1

It is, therefore, the primary object of this inveny ;tion to provide a position light which will give not only thehorizontal light spread, e. g., 140,

. -Whi ch existing Government regulations require, but will also present an intense light to an overtaking aircraft moving in the zone of greatest danger, namely, close to-the flight path of the preceding aircraft.

I have found that the use of an improved reiflector system and critical positioning of the elec tric light source with respect thereto, will produce not only wide anglebeams of direct light, but also a multiplicity of wide angle reflected beams, which increase markedly the intensity of the light when I viewed within the danger zone, as'above explained.

Referring to thedrawings,

Figure 1 is a section of my improved position lightwith parts in plan and viewed from the-top, a

part of the wall of the housing being cut away;

Figure 2 is a front elevation with the cover glass removed; H

Figure 3 is a side elevation partly in section with part of the housing broken away;

Figure 4 is a detail elevational view of'the refiector unit; 2

Figure 5 is a view similar to Figure 1 showing a modification; I

Figure 6 is a sectional plan view showing another modification in which the reflecting surface is carried on the electric light bulb;

Figure '1 is afront elevation of the position light the cover glass removed; Figure Bis a view similar to Figure 6 showing a 'further modification of the construction shown in' that figure, and

Figures 9 and 10 are elevational face views of preferred formsrof reflector surfaces which may be used in connection with Figures 1 to 8.

The preferred form of general construction is illustrated in Figures 1 to 3 and the preferred type of reflector is illustrated in Figure 10. In this construction, the housing the aircraft as by means of screws and faring in the usual'way. The housing is cylindrical and carries angular light cut-oif shields H which are detachab-ly or fixedly secured thereto inany suitable manner. Such shields may consist of a single ing portions l2 projecting band of metal riveted to the housing periphery thereof and having arcuate light shieldbeyond the housing .to provide the opposed-light shields, for restricting "the horizontal light'spread as legally required.

The outer arcuate edges of the horizontal light shields meet at diametrically'opposed points l3 so that there is no limitation at these points to the 7 "vertical light spread. It will be observed that the horizontal light spread ispositively limited by the light shields ll I and the increase in vertical light spread is gradual toward the points l3.

' I have discovered'that when the structure just described is utilized with a concave reflector having a multiplicityo'f spaced reflecting protuber- 'ance's, and an electric light" source is located at ,the focal point F'of the reflector, improvedibeam candle poweris ,o

tained. Moreover, and at the same time, official requirements withres-pect to 7 horizontal light spread are fully complied with.

The improved construction has been demonvstrated successfully and will solve the problems created by the, constantly increasing rate of speed of aircraft and the increasing volume of airtraf- 1, s'tallati'on',

' candescent lamps having. a point source andstandard light center lengths.

The construction does .not require any structural modifications of the'air'craft for purposes of inand does not depart from the Civil Aeronautics Administration regulations Moreover, the invention can be utilized with present position light installations and withconventional infilament In order to obtain the improved results, a reflector is employed of the concave type,-as shown at 15. Thisreflector-may be either spherii 'cal or parabolic. The concave reflecting portion "l 5 may be provided with a substantially cylindrical, \vallilt, the reflecting or silvered surface of 16 .being continuous.

the concave portion l5 and cylindrical portion Formed on the continuous reflecting wall l 5 l 61are a multiplicity of in- ;wardly extending spaced, protuberances as shown in Figures 2, '7, 9 and 10 Thesemay'be of any desired form, but preferably are in the form of mounds or prisms molded or struck up from the material of'which the reflector is made, e. g.,glass, metal, plastic, etc.

This reflector is suitably united, as by soldering, to a standard bayonet socket, orother lamp socket, as-shownat l8, and

Ill about the 2,447,302 v 3 4 the reflector and socket constitute a unit which edge IQ of the reflector and that the light source may be built into the original structure or may be 2| coincides with the focal point of the reflector. introduced to mountings already in position on The filament 2| is disposed, as in the construethe aircraft, as shown in Figure 4. tion in Figure 1, at a point which substantially The protuberances I1 may vary i size ith coincides with a diametric line connecting the relation to the size of the reflector. Preferably, Outer edge of t housing o at e shields such proportions are employed wherein the pro- U l p p y tr l t r ontal g t tuberanees are from to A," i di m t or spread of direct beams, as previously described. width at their bases in a, reflector having a t- Otherwise, the construction is similar to that side diametenbf ZT The protiuberancesiareapref- ;."shown imFigure 1. I Y

erably "spaced tt'parta distancg'varying from iif rle' to' fvigula-fipthedampdtself is proequal to their diameters or widths to a distance vided with a concave reflecting surface 26 of the two or more times their diameters or widths-as p l r p r l typ h rf c is suitshown in Figure 10, and preferably are arranged w b lti and is provided With a p ty in staggered relation as shown. The wide spac spaced reflecting protuberances I1. ing in Figure 9 represents one hmitvwmleiith sfiiilherooncave reflecting portion 26 and the proclose spacing in Figures 2 --arnd '1"repr-iesentithe bstanc sa epr i pr u d by m ldin opposite limit. theglassof "which the lamp is formed. It will The focal point F of the concave pontioni'iIt'sof rbennoted n thisc nstructi n t t t e fOcal point the reflector may be located on th xi of th Q0 of the reflecting surface 26 is located on the axis eflector latwarying pointsfdepending ion. the .1. of.- s. h reiilec oh.and adjacent a line projected rdius Fof'thef'reflctoi e;- g-.-,-f=rom a position- .out- .-diam r al y...a r s out ed 0f t e side': ofrther marginal ledge- |9wr0f the cylindrical Lfie as show at; 8. The filarnent 2 3 coin- ""Wal lIIicto a position-afljacent a'diametric line -c'ides with ith iqc po nthan t e shields -ll 'firoject'ed across:the-zmarginala-edge =of-the 'cylin- ;...limit the horizontalspread, as required y eggistmdricalr'wall'. In -theconstructionishownoin Fig- Qing re ulations. ji-flheishield l l re imilar o urel;the focal -point Fiofi-theconcave portion. [5 those previously described, and the construction 3coihcidesWi-th'the positiomot thfilament ZI of and. operation of this position light is in accordthe incen ides aent=-lamp-22. ance with; that described in-connection with 1 ig- A rIt-willbe;observedt-that the.arcuate edges '23 ures' 1 to 5.

of-the light;shields lleextend beyond or in 'ad- Referring to Figures '7 and 8, the concave re- I *va'nceofr-thedight-sourc ZILwhereby to constifleeting surface 26 "of the-lamp is-extended to ;=tute angular...rlight cutofi. means. for horizontal provide a substantially spherical Wal1-13 0sirnilar beams of .directnlightefrom the .li'ght source i2I. to the wal'lflfiof the'construction-shown in -Fighat is', thilightshilds" I I1 areisof disposed as ;;;;'ure 1. In othen words, the lamp is molded to positively l' torest'iict" the horizontalilight spread include a reflectingsurface comprising theconjggf directebarns offlightifi'omthe'filament 2|. to cave portion 26' and the =sphericahportionwfl I 1 i0 "Atitli'pisrittimejithe bfiicial regulations *which are suitably silvered and include a multiof'th Civil Aerohautics'Admimstration require plicity of spaced reflecting protuberances l'hhln -"thaftlf hbri'zon'talli'ght spreadt'b'elimited to140; ;.-=this construction thev'foc'al point ofltheconcave iahd 'theco'ristructio'r'fof Figure 1 inactualusehas portioh zfileoincides .withtherposition. of the filadef trated"chrnplete"compliance with -these 1 ment. 32-adjacent aniline projected. acrossthe 'rdiiiiemehts. edgeat the--outer diameten of.- the cylindrical The"vertical""lightfspi'adwillgradually" inreflecting-walla :?2The shields I Iv are. positioned fiercest from 40 ttff180 durnto themerging 01:, ahd operate in thehsame.manner..as,=described in t'ht5*r'g'iitered'g'e's"'il3"'of the" ShibIds -II- to the diaconnection.-with: Figures 1 to 6. 'ir'i-ti-li:ally *epposed -points -l3i prvious y -men In the preferredeconstruction;the;shields II. mmtr6 which restricjjmthe horizontal-spread, are P1 A light-transmitting cover glass 24 ofwa'ny .ablyvnotaprovided.- with a mirr-ored or .silv.ered coloi oi shape ivill -be employed iii thee surface.

suaP' i he 0 s i p t u fi Theiefieotivenessi'of; the .presentrinvehti li has From the foreiz'oirigl it will be xobservedsathat been demonstrated both from the stahdpoint of fizofithbhinfi ofidirechlli ght arei cuteofl: or increased .beam;,;candle powe r a s n as xt orifiiie d ii the fieiiuired angular'ispread byzrthe ease of installation;and-zpfi fmflhfih O f assembly, lffilcfs l I- vfcire'o'ver?by-lr-eeaisor-r ofri'the concave; 55.;notwithstandin ythcyihration. which is normally refldtor and tli'ef muitiplicityofxerefleoting proencountered in the operation of aircraft.

tuberances, therea are produced'a greatinumber rite-will. bfrsappreciatedthorn/the;- reaping 01 reflected heams encompassin a --w "ang1e scription that in any of the forms o f therinyenanwtheir add-itiorr to theaparallel beams from the tion -a nstrvuetionis provided .w herein t I e focal o'ncave reflector and th'edirect beams. iromthe a -mint oj thesnefle ctqr is lgcated a t a ,p qintj r om w light source markedly increasestheibeamicandle outside of :thowreflfi t li 8-S 0Wn in E'igure 5; to pewerohthe'light. smoother-words, -the..entire a; poinhon or. adjacent,. i. e ,close to .andwithin i; reflecting surface (lithe reflector is (utilized and or., -without ling ,prpjec ting ,agrtoss the outside when viewedby the"pilot' of an overtaking ship fam ter ch me-reflector {The point of. theelecfwhqfseifiightpath fisclo'se t'o'that of the'precedin g trio,llight source -coincides ,With this focal. point fa'lir'ciaft", a'ii'.ii'itense"illuminatioh'from-the entire 0f the reflector. The presence of thaprotuben -r neem face is presented? Atthe s'ametime, ances onethe.reflecting sunfaqe,whichproduce a -"";tl i light 5 ields II" corlfin" the-horizonta-l spread ,-,-Mmu1tip1icity. qfi wide angle h eams of,. less ..spread "f Within-tli' requiredlimits. than the beams of -rect,.light ino jfiase th ,in-

P 'In Ffg'ure o there is illo'stratedi aflmOdifiCEtiOD to tensity enorxnously when...the;.p int lightrsource wh'eieifi the' eynri icaTreflecting fwallr I=6= is ....and.the.iQQal,point qf th ereflectpncoincide Also,

"omitted and a simpl'e-iconoave reflector I ofa-the it will be noted that the focal; point and th iep'h'erical or psfrabolic typedsi employed. In this n of.,the .,-light,.nsource -coincicle with :-'-="coristruction,'it Will-be noted that the.focal;point .diametricdinepro ected so as .tgpofgi h bf the-reflector extendsrbeyond the marginal; Z5.,,posed,,rnerger points or rneeting ends source and being located trcuate edges 23 of the shields II. By reason of .he construction shown and described, the reuired angular cut can be positively controlled.

Any suitable type of light transmitting cover 24 rnay be used.

Referring to Figures 2 and 7 where the protuberances are closely arranged, there is produced wide angle reflected beams extending in a multiplicity of directions with a reduction in the number of parallel beams type reflector. The reflector of Figure 9 produces narrower beams with less spread because there are fewer protuberances to direct the light into wider angles but there is an increase in the number of parallel beams from the concave reflector. The structure of Figure 10, which is preferred, is intermediate in its effect between the reflectors of Figures 2 and 7, on the one hand, and the reflector of Figure 9, on the other hand.

It is to be understood that the forms of the invention shown and described are merely illustrative of a preferred embodiment and that such changes may be made without departing from the spirit of the invention and the scope of the claims, as fall within the purview of one skilled in the art.

I claim:

1. An aircraft position light comprising an electric light source, a concave reflector, said reflector having a multiplicity of spaced inwardly extending reflecting protuberances, angular cut-off means for limiting the horizontal spread of beams from said light source and reflector, and a light transmitting cover, the focal point of said reflector coincidingwith the point of said light reflected from the concave between a point outside of the reflector to a point adjacent a line projected across the outer diameter of the reflector, said cut-ofi means comprising a pair of shields having arcuate edges whose ends meet at diametric points; the focal point of said reflector and the point of said light source substantially coinciding with a point on a diametric line connecting the meeting ends of the arcuate edges of said shields.

2. An aircraft position light according to claim 1 wherein said concave reflector and said protuberances produce a multiplicity of wide angle beams of less spread than the beams of direct light from said light source. v 3., An aircraft position light according to claim 1 wherein the reflecting surface and protuberances are carried by the bulb enclosing said light source.

CHARLES ADLER, JR.

REFERENCES CITED UNITED STATES PATENTS Number Name Date 514,739 Timbrell et al Feb. 13, 1894 1,267,884 McKeever May 28, 1918 1,389,180 Bennett Aug. 30, 1921 1,463,677 Davis July 31, 1923 1,693,453 McElroy Nov. 27, 1928 2,084,999 Birdseye June 29, 1937 FOREIGN PATENTS Number Country Date 433,948 Great Britain 1935 

